The present invention relates to devices for soldering cable conductors. Specifically, a soldering fixture is provided which simultaneously cools a cable conductor and maintains the cable conductor and a connector in an aligned position during a soldering operation.
Soldering techniques for attaching the cable conductors to connectors are well-established in the industry. These techniques provide for the joining together of conductors and connectors using molten solder. In smaller-gauge wires, common problems resulting from application of heat are overcome using anti-wicking tools. These devices maintain the heat flow in a conductor at a safe level, such that the heat does not transfer to that portion of the cable which is not being soldered. Further, these tools prevent wicking of the solder, i.e., solder travel through capillary action into that portion of the conductor which is outside the joint formed with the connector.
These techniques have been well-developed with respect to small-gauge wire and connectors. However, as the size of the cable conductors increase above 8-gauge, significant difficulties are encountered in maintaining the larger-diameter cables safe from excessive heat and from the problem of solder wicking. Further, the larger-mass cable conductors and connectors require much more heat, and are slower to cool than smaller conductors and the correspondingly smaller connectors. During the cooling time for the solder joint, the two pieces to be joined together must be maintained rigidly supported so that no relative movement occurs between the connector and conductor. Any such movement will result in an inferior joint being formed between the connector and conductor.
Thus, it is important during the tinning operation of large-diameter cables, i.e., those in excess of 8 gauge, to adequately heat sink the cable conductor during a tinning operation. Further, during the operation of sweating a connector to the cable, which requires large amounts of heat, it is necessary to maintain the connector and conductor in rigid alignment until the solder has safely cooled to create a rigid bond with the conductor and connector.
SUMMARY OF THE INVENTION
It is an object of this invention to provide a soldering fixture to support a cable conductor during a soldering operation.
It is a more specific object of this invention to provide a fixture which supports a large diameter cable during a conductor tinning operation.
It is yet another object of this invention to provide a soldering fixture for supporting a cable conductor during the soldering of a connector to the conductor.
It is still another object of this invention to provide a fixture which holds a conductor and a connector in rigid alignment during the soldering process.
These and other objects of the invention are provided by an apparatus which supports a large cable conductor during a soldering operation. The apparatus includes a heat sink associated with a cable conductor support for maintaining the portion of the cable adjacent the conductor cooled during a soldering operation.
In accordance with the preferred embodiment, the heat sink includes two channels of different dimensions for supporting two sizes of cables. The heat sink includes a chamber for receiving a pumped coolant. The pumped coolant is recirculated through a radiator. The heat sink maintains the cables at a safe operating temperature during the solder operation, avoiding any damage to the cable shields or insulation.
The heat sink supports the cable conductor in alignment with a tool elevator which moves towards and away from the supported conductor along an axis of the conductor. A solder pot may be supported on the tool elevator which can be raised along the axis of the conductor until the conductor is immersed in molten solder. Alternatively, the tool elevator may support a chuck for holding a connector which is being soldered to the cable conductor.
In a preferred embodiment of the invention, a common heat sink supports one of two different sizes of cable during a soldering operation. Two tool elevators are provided, which can raise and lower a tool along the axis of the cable conductors. Depending on the wire size, either tool elevator may include a solder pot having an axis coincident with one of the supported cable conductor axes, or a connector chuck having an axis coincident with the supported conductor axis.
Each tool elevator can be positioned to a plurality of vertical positions, permitting the tool supported on each tool elevator to be accurately aligned with a cable conductor. The alignment may be maintained during the solder operation to avoid any misalignment before the solder cools.
DESCRIPTION OF THE FIGURES
FIG. 1 illustrates a front view of a soldering fixture in accordance with the preferred embodiment.
FIG. 2 is a side view of the soldering fixture of FIG. 1.
FIG. 3 shows in greater detail a plan view of the tool fixture of FIG. 1.
FIG. 4 is a section view of FIG. 3 taken along lines A--A.
FIG. 5 is a second section view of the apparatus of FIG. 3 used during a tinning operation.
FIG. 6 illustrates the solder fixture of FIG. 1 having a connector chuck connected to the end of the elevator.
FIG. 7 illustrates a first step in the process of soldering a connector to a cable.
FIG. 8 illustrates a second step for soldering a connector to a cable.
FIG. 9 illustrates a third step in the process of soldering a connector to a cable.
FIG. 10 illustrates a fourth step in soldering a connector to a cable conductor.
FIG. 11 illustrates a fifth step in soldering a connector to a cable.
FIG. 12 is an exploded view of the
heat sink 14.
FIG. 13 illustrates in detail the cooling system used to pump coolant through the
heat sink 14.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to FIGS. 1 and 2, there are shown front and side views of a cable soldering fixture in accordance with a preferred embodiment of the invention. The cable soldering fixture includes a
heat sink 14 which is cooled by a pumped
fluid entering inlet 17 and exiting
outlet 16. The fluid is pumped by a
cooling system 15 which releases the heat contained within the coolant through a radiator.
The
heat sink 14 supports one of two different size cables so that exposed conductor of this cable lies along the axis of one of the two
tool elevators 22 and 23.
Tool elevators 22 and 23 are supported for vertical movement by
guide plates 20 and 21. The entire structure of
guide plates 20, 21 and
heat sink 14 are supported by
vertical side plates 12 and 13.
The alignment of the
tool elevators 22 or 23 with the axis of the conductor permits various tools used during the soldering process to be accurately aligned with respect to the axis of a cable conductor.
Each of the
elevators 22 and 23 includes a
handle 25, 26 which can position the elevator vertically with respect to a supported cable conductor. A
panel 19 supported by each of the
vertical side plates 12 and 13 includes a plurality of staggered
slots 29, which can receive a
respective handle 25, 26 of a tool elevator.
Panel 19 is supported to the
guide plate 21 with
suitable fasteners 28.
The staggered
slots 29 permit vertical positioning of the
handle 25 and therefore the positioning of the tool elevator with respect to the supported conductors.
Referring now to FIG. 3, the positioning mechanism for maintaining each of the tool elevators in a respective vertical position is shown. The two vertically extending
slots 29 and 30, have a plurality of
positions 32 and 33 for fixing the position of the
handles 25 and 26. Thus, during a soldering operation, the vertical position of the tool-bearing end of the tool elevator can be maintained fixed to permit solder cooling or other processes to take place.
In operation, the device in accordance with FIGS. 1 through 3 can be used to either tin cable conductors supported in the
heat sink 14, or to position a connector over the conductor during a soldering operation, and maintain the connector positioned relative to the conductor until the connector has cooled.
Referring to FIG. 4, the axis of the
tool elevator 22 is coincident with the axis of a groove 14c provided in the surface of
heat sink 14. As will be evident from other Figures, the cable supported within groove 14c also has an axis coincident with the
tool elevator 22 axis.
At the top of the
tool elevator 22 is shown a
fixture 31, which provides a shoulder on which a tool may be supported.
The beginning steps of a tinning operation are shown in FIG. 5. A solder pot which has a
cavity 44 is connected to the
fixture 31. The cavity receives
molten solder 52. A
bi-metallic catch 46 is shown which is secured to the body of the
solder pot 44 with a
fastener 48. The
bi-metallic catch 46 maintains the
solder pot 52 connected to the
fixture 31. The
shoulder 50 of the
fixture 31 is grasped by the
tang 49 of the
bi-metallic catch 46. Thus, when the
pot 44 is heated to contain the
molten solder 52, the
tang 49 of the
bi-metallic catch 46 engages
fixture 31. Once the
solder pot 44 has cooled, the
bi-metallic catch 46 releases the
solder pot 44 from the
tool fixture 31.
The
solder pot 52 may be raised so that the
conductor 8 is tinned with the
molten solder 52. The sheath of the
cable 10 is protected from excessive heat as well as from wicking of the solder by the
heat sink 14. The
heat sink 14 includes an interior section 14b containing the coolant supplied through
inlet 17. The removable portion 14a of the heat sink is held in place with
screws 18, as will be evident from the remaining Figures.
The soldering fixture may also be used to position a solderable connector over a
tinned conductor 8. FIG. 6 illustrates the use of a
chuck 45 supported on the end of a
tool elevator 23.
Chuck 45 supports a
connector 46, which can be positioned during a soldering operation to receive the
conductor 8. FIG. 7 illustrates the
chuck 45, and
connector 46 before positioning for a solder operation.
FIGS. 8, 9, 10 and 11 illustrate the process of soldering a connector to the
conductor 8. In FIG. 8, the
connector 46 is heated and includes a quantity of flux and solder therein. As the solder melts, the
handle 26 is raised in FIG. 9 to position the
connector 46 to receive
conductor 8. FIG. 10 illustrates the process of sweating the
connector 46 to the
conductor 8, using a blowtorch. In FIG. 11, the
conductor pin 46 is maintained in position, permitting the solder to cool. FIGS. 10 and 11 illustrate how the horizontal vertically ascending
slots 29 in the
panel 19
support handle 26, so that no movement is experienced during the final critical steps of soldering the
connector 46 to the
conductor 10.
FIG. 12 is an exploded view of the
heat sink 14. The
heat sink 14 includes a coolant chamber 14b connected to
inlet 17 and
outlet 16. One of the grooves 14c
1 and 14c
2 in the face of the coolant chamber 14b receives the cable bearing the conductor to be soldered. The cable is held in place by one of ridges 14d
1, 14d
2 in the clamping surface 14a. The
fasteners 18, grooves 14c
1, 14c
2 and ridges 14d
1, 14d
2 in the clamping surface 14a captivate first and second conductors, so that the axis of the conductors is coincident with the axis of the tool elevators.
The pumped cooling system is illustrated more completely in FIG. 13. The system includes the
heat sink 14 connected through its inlets and
outlets 17 and 16, respectively, to a
liquid pump 53 and liquid/
air heat exchanger 54. The
liquid pump 53 pumps fluid from a
liquid reservoir 59 through the cooling chamber 14b of the
heat sink 14. Heat removed from the cable during the soldering operation is exchanged with the outside air as the coolant is pumped through the
heat exchanger 54.
Fan 55 creates an air flow which transfers the heat from the pumped coolant as it passes through
heat exchanger 54 to the ambient air.
Thus, the device in accordance with the preferred embodiment, will maintain the temperature of the cable adjacent the region to be soldered at a safe temperature, avoiding solder wicking and any damage to the sheath or insulation of the cable. The device will also maintain the cable and connector in rigid alignment. Those skilled in the art will recognize yet other embodiments of the invention, described more particularly by, but not limited to, the claims which follow.